Semiconductor devices that include Hall elements are used in various electronic equipment such as cellular phones. In a cellular phone, the semiconductor device may be used to control the light source of the display of the phone in a manner such that the light source can be turned on or off in accordance with the opening or closing of the phone. The recent trend toward thinner electronic equipment (e.g., cellular phone) requires for height reduction of the incorporated semiconductor devices.
Japanese Patent No. 5676826 discloses a semiconductor device that includes a Hall element (which may often be referred to as “pellet”). The semiconductor device realizes height reduction by arranging an insulating layer in such a manner that the insulating layer is in close contact with the reverse surface of the pellet and exposed from the reverse surface of the sealing resin. However, since the heat dissipation performance of the insulating paste is relatively low due to its material characteristics, heat is likely to build up inside the semiconductor device during the operation of the pellet, thereby to hinder the performance of the pellet.